A ball-lock connector of the type that a connector and a counterpart connector are locked into a connected state is already known (for example, Patent Document 1 which will be described below (Japanese Patent Application Laid-Open No. Hei9-92395).
The conventional connector which is disclosed in Patent Document 1 is configured by comprising a ball support hole which is formed in a cylindrical fitting part disposed in a connector housing so as to open to both of its inner and outer peripheral surfaces, a lock ball which is housed in the ball support hole such that it can radially displace and cannot slip off to the side of a peripheral surface corresponding to a counterpart connector and locks the connectors together into a fitted state by bringing a part which is protruded toward the peripheral surface of the cylindrical fitting part into engagement with the counterpart connector, an elastic engaging member which is radially elastic-displaceable between an engagement position where it abuts against the lock ball which is in a state that it is engageable with the counterpart connector from the side opposite to the counterpart connector, and a retraction position where detachment of the lock ball from the counterpart connector is allowed, and a deflection restraining member that can restrain elastic deflection of the elastic engaging member to the retraction position.
In the connector disclosed in Patent Document 1, a cylindrical locking operation member is fitted on an outer periphery of the cylindrical fitting part so as to be axially movable. Then a plurality of pieces of elastic engaging members are formed integrally with this locking operation member so as to protrude forward from positions corresponding to the plurality of ball support holes in its front end edge.